From patchwork Fri Aug 23 07:36:49 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Grzeschik X-Patchwork-Id: 13774709 Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [185.203.201.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8BE4513C820 for ; Fri, 23 Aug 2024 07:37:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.203.201.7 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724398625; cv=none; b=qIEmW035c5Rl0lfkL2hii6KQrGDoV9lBVv0L2yJWaVkizwA7aSFcLkkE4HjZ+ZpnIckJBT7+fDrLM7mssfwRbQtQevU/7ITEcJXNMrpgfoxZR5TTlvWSq8mtnXB7E6gvJKQ13fM0qhVyXE6OB9zVamvWhRUrDjvrHweMuWRLOts= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724398625; c=relaxed/simple; bh=YJ/X/FPDMtc0rxjTRoovP47LcQzmK0QLxaRnX/yAJtE=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=HK09fuc53IMHjdM40OW0P8QLdpMsk0zl+OLZIBegAHjDTczK8ilrtpQPJyys2cbjgb3fBS4xv72AHuyiIcHMIketddfMYUqaKlrs29JirbPGuQ5EsNCqrJrE0YXzggE25WYANjiGLJRbzIPnUxudIR427GYtHdeouv6fDfwAADg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de; spf=pass smtp.mailfrom=pengutronix.de; arc=none smtp.client-ip=185.203.201.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pengutronix.de Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1shOqr-0004KU-Kz; Fri, 23 Aug 2024 09:36:53 +0200 Received: from [2a0a:edc0:0:1101:1d::ac] (helo=dude04.red.stw.pengutronix.de) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1shOqn-002R4O-6I; Fri, 23 Aug 2024 09:36:49 +0200 Received: from localhost ([::1] helo=dude04.red.stw.pengutronix.de) by dude04.red.stw.pengutronix.de with esmtp (Exim 4.96) (envelope-from ) id 1shOqn-00AtQT-0M; Fri, 23 Aug 2024 09:36:49 +0200 From: Michael Grzeschik Date: Fri, 23 Aug 2024 09:36:49 +0200 Subject: [PATCH v9 3/3] tools: usb: p9_fwd: add usb gadget packet forwarder script Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240116-ml-topic-u9p-v9-3-93d73f47b76b@pengutronix.de> References: <20240116-ml-topic-u9p-v9-0-93d73f47b76b@pengutronix.de> In-Reply-To: <20240116-ml-topic-u9p-v9-0-93d73f47b76b@pengutronix.de> To: Eric Van Hensbergen , Latchesar Ionkov , Dominique Martinet , Christian Schoenebeck , Jonathan Corbet , Greg Kroah-Hartman Cc: Andrzej Pietrasiewicz , v9fs@lists.linux.dev, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, kernel@pengutronix.de, Michael Grzeschik , Jan Luebbe X-Mailer: b4 0.12.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=12498; i=m.grzeschik@pengutronix.de; h=from:subject:message-id; bh=YJ/X/FPDMtc0rxjTRoovP47LcQzmK0QLxaRnX/yAJtE=; b=owEBbQKS/ZANAwAKAb9pWET5cfSrAcsmYgBmyDwQ6OIrkwfT5Va0sCsp/hMeghDAnD/Db5bSP 1tl86+bJpGJAjMEAAEKAB0WIQQV2+2Fpbqd6fvv0Gi/aVhE+XH0qwUCZsg8EAAKCRC/aVhE+XH0 qwgSD/9m60eYygMBM1ApoRne8fkQyls+s3CrjHUUsDe1WDgaJA4Rm1teShJZAQJ00x8zH7U9HYl KIjI80s8Ds/ddKjQwPFF02SHtmImEssK3lbZvWLZcF/l8+kt7rXmGAinTDLcJbXWFMB6urNBQ9y A2E9aHo1jheRLBx0JSol7Bd/SbSReENwPg591YcaymHIyPY7kqOVlURPMrknRFiaJmvxu7AGD/6 aRd25OGJDBXqqyWLkRIOKFkroKD/cf7J2WAOrIqcXFg31r5J6Q4nSqgdVF4VmxhzAs7KKmwKpjs OlxYyaLlvlr3S8WnOs1G4DeoBol40km1e2oJqzgIeXOjSClPta8MYN7d3weTFtj9WGseT2nKPFR Kf7XBrQvrMhtHAGLScjYhX7CVZ5xVOIcuLbpRo+Y7Nk+K3LFeF3eJCdjyu/CBhWwc5miyjXB0Ij 3s5kKlRyqWe4ZfiXBGZWJgscFeoOLPrVCTQxPwcaXhMsW0Et3re5xPrFA+KjlsFctCQYaruRzDy Hl0cp8VaC8PP18WuomznGh1js92uLvXFHuWAnGAzusisCfHEziX2Zr8TYZemEEmgXKGepPO42om vXWyGOLhMIunW4jhKPj8QWBjSTT1SPF5Favf5HBdrw96XXqG1bCwwsmWfEmBIvbMh466jB4dn5h wKP9SUDE0Cu3vHQ== X-Developer-Key: i=m.grzeschik@pengutronix.de; a=openpgp; fpr=957BC452CE953D7EA60CF4FC0BE9E3157A1E2C64 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: m.grzeschik@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-usb@vger.kernel.org This patch is adding an small python tool to forward 9pfs requests from the USB gadget to an existing 9pfs TCP server. Since currently all 9pfs servers lack support for the usb transport this tool is an useful helper to get started. Refer the Documentation section "USBG Example" in Documentation/filesystems/9p.rst on how to use it. Signed-off-by: Jan Luebbe Signed-off-by: Michael Grzeschik --- v8 -> v9: - v7 -> v8: - v6 -> v7: - v5 -> v6: - set path parameter to None when unused v4 -> v5: - updated documentation for new subcommands list/connect - run ruff format - make vid and pid parameterized - add list as subcommand to scan for devices - move connect to extra subcommand v3 -> v4: - v2 -> v3: - v1 -> v2: - added usbg 9pfs detailed instructions to 9p.rst doc --- Documentation/filesystems/9p.rst | 41 +++++++ tools/usb/p9_fwd.py | 243 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 284 insertions(+) diff --git a/Documentation/filesystems/9p.rst b/Documentation/filesystems/9p.rst index 10cf79dc287f8..2cc85f3e8659f 100644 --- a/Documentation/filesystems/9p.rst +++ b/Documentation/filesystems/9p.rst @@ -67,6 +67,47 @@ To mount a 9p FS on a USB Host accessible via the gadget as root filesystem:: where is the tag associated by the usb gadget transport. It is defined by the configfs instance name. +USBG Example +============ + +The USB host exports a filesystem, while the gadget on the USB device +side makes it mountable. + +Diod (9pfs server) and the forwarder are on the development host, where +the root filesystem is actually stored. The gadget is initialized during +boot (or later) on the embedded board. Then the forwarder will find it +on the USB bus and start forwarding requests. + +In this case the 9p requests come from the device and are handled by the +host. The reason is that USB device ports are normally not available on +PCs, so a connection in the other direction would not work. + +When using the usbg transport, for now there is no native usb host +service capable to handle the requests from the gadget driver. For +this we have to use the extra python tool p9_fwd.py from tools/usb. + +Just start the 9pfs capable network server like diod/nfs-ganesha e.g.: + + $ diod -f -n -d 0 -S -l 0.0.0.0:9999 -e $PWD + +Optionaly scan your bus if there are more then one usbg gadgets to find their path: + + $ python $kernel_dir/tools/usb/p9_fwd.py list + + Bus | Addr | Manufacturer | Product | ID | Path + --- | ---- | ---------------- | ---------------- | --------- | ---- + 2 | 67 | unknown | unknown | 1d6b:0109 | 2-1.1.2 + 2 | 68 | unknown | unknown | 1d6b:0109 | 2-1.1.3 + +Then start the python transport: + + $ python $kernel_dir/tools/usb/p9_fwd.py --path 2-1.1.2 connect -p 9999 + +After that the gadget driver can be used as described above. + +One use-case is to use it as an alternative to NFS root booting during +the development of embedded Linux devices. + Options ======= diff --git a/tools/usb/p9_fwd.py b/tools/usb/p9_fwd.py new file mode 100755 index 0000000000000..12c76cbb046b7 --- /dev/null +++ b/tools/usb/p9_fwd.py @@ -0,0 +1,243 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: GPL-2.0 + +import argparse +import errno +import logging +import socket +import struct +import time + +import usb.core +import usb.util + + +def path_from_usb_dev(dev): + """Takes a pyUSB device as argument and returns a string. + The string is a Path representation of the position of the USB device on the USB bus tree. + + This path is used to find a USB device on the bus or all devices connected to a HUB. + The path is made up of the number of the USB controller followed be the ports of the HUB tree.""" + if dev.port_numbers: + dev_path = ".".join(str(i) for i in dev.port_numbers) + return f"{dev.bus}-{dev_path}" + return "" + + +HEXDUMP_FILTER = "".join(chr(x).isprintable() and chr(x) or "." for x in range(128)) + "." * 128 + + +class Forwarder: + @staticmethod + def _log_hexdump(data): + if not logging.root.isEnabledFor(logging.TRACE): + return + L = 16 + for c in range(0, len(data), L): + chars = data[c : c + L] + dump = " ".join(f"{x:02x}" for x in chars) + printable = "".join(HEXDUMP_FILTER[x] for x in chars) + line = f"{c:08x} {dump:{L*3}s} |{printable:{L}s}|" + logging.root.log(logging.TRACE, "%s", line) + + def __init__(self, server, vid, pid, path): + self.stats = { + "c2s packets": 0, + "c2s bytes": 0, + "s2c packets": 0, + "s2c bytes": 0, + } + self.stats_logged = time.monotonic() + + def find_filter(dev): + dev_path = path_from_usb_dev(dev) + if path is not None: + return dev_path == path + return True + + dev = usb.core.find(idVendor=vid, idProduct=pid, custom_match=find_filter) + if dev is None: + raise ValueError("Device not found") + + logging.info(f"found device: {dev.bus}/{dev.address} located at {path_from_usb_dev(dev)}") + + # dev.set_configuration() is not necessary since g_multi has only one + usb9pfs = None + # g_multi adds 9pfs as last interface + cfg = dev.get_active_configuration() + for intf in cfg: + # we have to detach the usb-storage driver from multi gadget since + # stall option could be set, which will lead to spontaneous port + # resets and our transfers will run dead + if intf.bInterfaceClass == 0x08: + if dev.is_kernel_driver_active(intf.bInterfaceNumber): + dev.detach_kernel_driver(intf.bInterfaceNumber) + + if intf.bInterfaceClass == 0xFF and intf.bInterfaceSubClass == 0xFF and intf.bInterfaceProtocol == 0x09: + usb9pfs = intf + if usb9pfs is None: + raise ValueError("Interface not found") + + logging.info(f"claiming interface:\n{usb9pfs}") + usb.util.claim_interface(dev, usb9pfs.bInterfaceNumber) + ep_out = usb.util.find_descriptor( + usb9pfs, + custom_match=lambda e: usb.util.endpoint_direction(e.bEndpointAddress) == usb.util.ENDPOINT_OUT, + ) + assert ep_out is not None + ep_in = usb.util.find_descriptor( + usb9pfs, + custom_match=lambda e: usb.util.endpoint_direction(e.bEndpointAddress) == usb.util.ENDPOINT_IN, + ) + assert ep_in is not None + logging.info("interface claimed") + + self.ep_out = ep_out + self.ep_in = ep_in + self.dev = dev + + # create and connect socket + self.s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) + self.s.connect(server) + + logging.info("connected to server") + + def c2s(self): + """forward a request from the USB client to the TCP server""" + data = None + while data is None: + try: + logging.log(logging.TRACE, "c2s: reading") + data = self.ep_in.read(self.ep_in.wMaxPacketSize) + except usb.core.USBTimeoutError: + logging.log(logging.TRACE, "c2s: reading timed out") + continue + except usb.core.USBError as e: + if e.errno == errno.EIO: + logging.debug("c2s: reading failed with %s, retrying", repr(e)) + time.sleep(0.5) + continue + logging.error("c2s: reading failed with %s, aborting", repr(e)) + raise + size = struct.unpack(" 0 + data = data[written:] + if size % self.ep_out.wMaxPacketSize == 0: + logging.log(logging.TRACE, "sending zero length packet") + self.ep_out.write(b"") + logging.debug("s2c: forwarded %i bytes", size) + self.stats["s2c packets"] += 1 + self.stats["s2c bytes"] += size + + def log_stats(self): + logging.info("statistics:") + for k, v in self.stats.items(): + logging.info(f" {k+':':14s} {v}") + + def log_stats_interval(self, interval=5): + if (time.monotonic() - self.stats_logged) < interval: + return + + self.log_stats() + self.stats_logged = time.monotonic() + + +def try_get_usb_str(dev, name): + try: + with open(f"/sys/bus/usb/devices/{dev.bus}-{dev.address}/{name}") as f: + return f.read().strip() + except FileNotFoundError: + return None + + +def list_usb(args): + vid, pid = [int(x, 16) for x in args.id.split(":", 1)] + + print("Bus | Addr | Manufacturer | Product | ID | Path") + print("--- | ---- | ---------------- | ---------------- | --------- | ----") + for dev in usb.core.find(find_all=True, idVendor=vid, idProduct=pid): + path = path_from_usb_dev(dev) or "" + manufacturer = try_get_usb_str(dev, "manufacturer") or "unknown" + product = try_get_usb_str(dev, "product") or "unknown" + print( + f"{dev.bus:3} | {dev.address:4} | {manufacturer:16} | {product:16} | {dev.idVendor:04x}:{dev.idProduct:04x} | {path:18}" + ) + + +def connect(args): + vid, pid = [int(x, 16) for x in args.id.split(":", 1)] + + f = Forwarder(server=(args.server, args.port), vid=vid, pid=pid, path=args.path) + + try: + while True: + f.c2s() + f.s2c() + f.log_stats_interval() + finally: + f.log_stats() + + +def main(): + parser = argparse.ArgumentParser( + description="Forward 9PFS requests from USB to TCP", + ) + + parser.add_argument("--id", type=str, default="1d6b:0109", help="vid:pid of target device") + parser.add_argument("--path", type=str, required=False, help="path of target device") + parser.add_argument("-v", "--verbose", action="count", default=0) + + subparsers = parser.add_subparsers() + subparsers.required = True + subparsers.dest = "command" + + parser_list = subparsers.add_parser("list", help="List all connected 9p gadgets") + parser_list.set_defaults(func=list_usb) + + parser_connect = subparsers.add_parser( + "connect", help="Forward messages between the usb9pfs gadget and the 9p server" + ) + parser_connect.set_defaults(func=connect) + connect_group = parser_connect.add_argument_group() + connect_group.required = True + parser_connect.add_argument("-s", "--server", type=str, default="127.0.0.1", help="server hostname") + parser_connect.add_argument("-p", "--port", type=int, default=564, help="server port") + + args = parser.parse_args() + + logging.TRACE = logging.DEBUG - 5 + logging.addLevelName(logging.TRACE, "TRACE") + + if args.verbose >= 2: + level = logging.TRACE + elif args.verbose: + level = logging.DEBUG + else: + level = logging.INFO + logging.basicConfig(level=level, format="%(asctime)-15s %(levelname)-8s %(message)s") + + args.func(args) + + +if __name__ == "__main__": + main()